If it has started to go rancid it will smell and taste bad.
Rancidity happens due to oxidation, so the more air it is exposed to the more likely it is oxidizing. Heat speeds along oxidation as well.
I sniff any oily things we might eat, like nuts (chopped or not), seeds, seed butters, nut butters, and I sniff almond oil which I use on my skin after a shower. Almond oil goes bad quickly. I buy fresh pressed and hope it lasts a year.